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 ###Instrução: Quantos anos Joined têm um Size menor que 417, e uma Classe IHSAA de A, e uma Escola de jac-cen-del?
 ###Tabelas: CREATE TABLE membership (membership_id AUTO_INCREMENT PRIMARY KEY, School VARCHAR, Location VARCHAR, Mascot VARCHAR, Size INT, IHSAA Class VARCHAR, County VARCHAR, Year Joined INT, Previous Conference VARCHAR) CREATE TABLE classification_leadership (classification_leadership_id AUTO_INCREMENT PRIMARY KEY, Stage INT, Winner VARCHAR, General classification VARCHAR, Points classification VARCHAR, Mountains classification VARCHAR, Young rider classification VARCHAR) CREATE TABLE 40_point_games (40_point_games_id AUTO_INCREMENT PRIMARY KEY, Number INT, Opponent VARCHAR, Box Score VARCHAR, Points INT, FGM - FGA VARCHAR, 3PM - 3PA VARCHAR, FTM - FTA VARCHAR, Assists INT, Rebounds INT, Steals INT, Blocks INT) CREATE TABLE doubles_finals_19_10-9 (doubles_finals_19_10-9_id AUTO_INCREMENT PRIMARY KEY, Outcome VARCHAR, Date INT, Tournament VARCHAR, Surface VARCHAR, Partner VARCHAR, Opponents in the final VARCHAR, Score in the final VARCHAR) CREATE TABLE first_division_final_table (first_division_final_table_id AUTO_INCREMENT PRIMARY KEY, Position INT, Team VARCHAR, Played INT, Drawn INT, Lost INT, Goals For INT, Goals Against INT, Goal Difference VARCHAR, Points 1 VARCHAR)  
SELECT COUNT Year Joined FROM membership WHERE Size < 417 AND IHSAA Class = a AND School = jac-cen-del